Firefox has gone to crap.

My firefox is kaput. When i open the page, it is blank, despite the fact that i have my settings on "open to homepage." second, my navigation bar and menu bar doesnt work despite having followed the directions to remedy this, and my bookmarks are all gone, and again the steps i found on this site did not help me. My address bar holds the first address i typed in during a session for the entire time I am online, and I cannot bookmark anymore.